What causes knee pain?

Knee pain - no swelling - no bruising -
very minor pain when walking upstairs
slight pain when walking but not much
hoping for slight sprain - had a fall 2 months ago and was a little sore - but it all went away - no other injury?

Brief Answer:
osteoarthritis
Detailed Answer:
hi teri,
as you are nearing 60 s , the possibility of osteoarthritis should be considered.
it may not be related to the injury.
I Suggest you to get an x ray of knee joint to see if everything is right
meanhile, avoid squatting, climbing up stairs etc.
you may use topical lubricants.